France was yesterday quick to play down the significance of an explosion in a nuclear waste recycling plant in the south of the country which killed one man and injured four others.

Ministers said the blast, close to the Marcoule nuclear power station, near Avignon, was an "industrial accident" and not an explosion in, or near, a nuclear reactor. There had been no radioactive leak and no need to evacuate workers or local people.

The explosion at the sprawling Marcoule site on the banks of the Rhone - one of the oldest and largest nuclear facilities in France - is nonetheless a political and economic embarrassment to the French government.

Since the calamity at the Fukushima plant in Japan in March, France has been at pains to reassure its citizens, and potential foreign buyers, of the safety of its own nuclear technology. Environmental groups called yesterday on the French government, traditionally secretive on nuclear questions, to allow "total transparency" and an independent investigation of the Marcoule blast.

The pressure-group France Nature Environnement (FNE), which has 3,000 member associations, said the accident "underlines the problems with control of nuclear risks in France". The significance of nuclear accidents has sometimes been obscured by French authorities in the past, FNE pointed out.

Famously, the French government announced in 1986 that the radioactive nuclear cloud from the Chernobyl explosion in the Ukraine had "stopped at the French frontier". A lengthy legal investigation of French official responsibility in covering up the effects of Chernobyl concluded last week that there was no case to answer.

Officials said that yesterday's explosion had occurred in an oven used to destroy or recycle feebly radioactive objects ranging from metal bars to tools and gloves. The oven was in the Centraco recycling plant at Codolet, part of a large complex of nuclear facilities that has grown up near to the Marcoule power station.

First reports said that there had been a leakage of radioactivity and that local people would have to be evacuated. This was rapidly denied. Detectors outside the complex had found no trace of a radioactive escape, officials said. The explosion was being treated as an "industrial accident" with no implications for the local population, said the Energy Minister, Eric Besson.

The French nuclear safety authority, the Autorite de Surete Nucleaire, said that the blast occurred in an oven which destroyed or recycled objects of "low or very low radioactivity". One worker had been burnt to death. Four others had been injured but had suffered no exposure to radiation.

Background

France is the most nuclear-dependent country in the world, with the lion's share of its electricity output - 79% - coming from the 58 nuclear reactors that dot the country. France is also a major exporter of nuclear power, treats nuclear waste from around the world, and state-owned nuclear giant Areva is one of the country's most prominent companies.